Einheitsdampflokomotiven

The German term Einheitsdampflokomotive, sometimes shortened to Einheitslokomotive or Einheitslok, means standard steam locomotive and refers to the steam engines built in Germany after 1925 under the direction of the Deutsche Reichsbahn-Gesellschaft. Their manufacture made extensive use of standard design features and components.

Following the merger of the state railways (Länderbahnen) in Germany into the Reich railway in 1920 and into the Deutsche Reichsbahn-Gesellschaft in 1924, the locomotive fleet of the new national railway administration still had 210 different types and classes of steam engine. This considerably hindered the flexible employment of locomotives within the railway network, and servicing and maintenance was very costly as a result of the large number of different spare parts that had to be stocked. In addition, production tolerances of individual components were so small that, often, even components for the same class of locomotive could only be used after further finishing work had been carried out.

On top of that, substantial reparations as a result of the First World War, 1914–18, considerably reduced the rolling stock of the German railways without regard to the variety of classes. Thus out of the 33,000 locomotives in the fleet (as at 1917), 8,000 had to be handed over. There was therefore a need to build new locomotives and to introduce a sensible degree of standardisation in procuring these new engines.

To that end a locomotive standards committee was convened by the Reichsbahn. Even representatives of the locomotive industry took part in this standardisation process. Initially the question was posed as to whether proven state railway classes should continue to be built or whether new, modern locomotives should be developed and ordered. Because the basic concepts for the new locomotives had not been decided, however, and in order to give the locomotive factories follow-on orders, it was decided in 1921 to continue to build proven state railway classes to begin with. These classes were given new Reichsbahn classifications. Amongst them were the Prussian P 8 (Class 38.10), the Prussian P 10 (Class 39), the Prussian G 12 (Class 58.10) and the Prussian T 20 (Class 95), all of which continued to be manufactured until 1925. The Bavarian S 3/6 (Class 18.5) was even procured right up to 1930. The Prussian G 12 (Class 58.10), which was not developed until 1917, effectively counted as the first German Einheitslok, because it was employed by almost all the state railways and built by several locomotive factories across the whole Reich.

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